Method getDrawableRegion

src/ui/widget.cpp:707–800

}

void Widget::getDrawableRegion(gfx::Region& region, DrawableRegionFlags flags)
{
  Widget* window, *manager, *view;

  getRegion(region);

  // Cut the top windows areas
  if (flags & kCutTopWindows) {
    window = this->window();
    manager = (window ? window->manager(): nullptr);

    while (manager) {
      const WidgetsList& windows_list = manager->children();
      WidgetsList::const_reverse_iterator it =
        std::find(windows_list.rbegin(), windows_list.rend(), window);

      if (!windows_list.empty() &&
          window != windows_list.front() &&
          it != windows_list.rend()) {
        // Subtract the rectangles
        for (++it; it != windows_list.rend(); ++it) {
          if (!(*it)->isVisible())
            continue;

          Region reg1;
          (*it)->getRegion(reg1);
          region.createSubtraction(region, reg1);
        }
      }

      window = manager->window();
      manager = (window ? window->manager(): nullptr);
    }
  }

  // Clip the areas where are children
  if (!(flags & kUseChildArea) && !children().empty()) {
    Region reg1;
    Region reg2(childrenBounds());

    for (auto child : children()) {
      if (child->isVisible()) {
        Region reg3;
        child->getRegion(reg3);

        if (child->hasFlags(DECORATIVE)) {
          reg1 = bounds();
          reg1.createIntersection(reg1, reg3);
        }
        else {
          reg1.createIntersection(reg2, reg3);
        }
        region.createSubtraction(region, reg1);
      }
    }
  }

  // Intersect with the parent area